add cf value of "current" stack to template vars

[jaffee]

This gives templates a way to reference the parameters under "cf" in a stack the
config file without referencing a stack name directly. The "currentstack" key in
the map passed to the template will contain the "cf" map of the stack which is
being generated.

In this way, a single template can be used by multiple different stacks and have
different outputs.

If you can think of a cleaner way to achieve something like this, please let me know. I'm also very open to changing the name "currentstack".

I'd also like to call out that this could be a backwards incompatibility if someone had a stack named "currentstack" already.

[daidokoro]

Hey Matt, thanks for this.

I believe I implemented something similar, you're able to reference which stack is calling a template by using {{ .stack }}, this however, only gives you the name of the stack calling the templates, you would need to use if-statements to swap values.

I think your method is better as the values are also accessible using {{ $.currentstack.etc }}.

So i'd recommend, overriding my {{ .stack }} functionality with this. Should just be removing line 632 in stack.go and changing currentstack to stack.

Thanks again :-)

[jaffee]

I've made that change:

I like the simplicity of your suggestion, but are you concerned that there will no longer be access to the current stack name?

I'm also hesitant since this is a breaking change to anyone currently using {{ .stack }}.

[daidokoro]

Ye, you're right, this will be a breaking change, but i'm still in beta, so no better time to do it :-)

The main reason I added {{ .stack }} was for the exact functionality you've added, so i'm more keen on going with your solution here, as it's a bit cleaner than an if-block and scales better.

Currently working on 0.60-beta, hopefully get it out later tonight, so i'll implement another keyword, possibly, {{ .stack_name }} to replace {{ .stack }}.

Thanks again Matt 👍